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Stiffness-damping matching method of an ECAS system based on LQG control 被引量:9
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作者 陈一锴 何杰 +2 位作者 M.KING 陈无畏 张卫华 《Journal of Central South University》 SCIE EI CAS 2014年第1期439-446,共8页
A novel method of matching stiffness and continuous variable damping of an ECAS(electronically controlled air suspension) based on LQG(linear quadratic Gaussian) control was proposed to simultaneously improve the road... A novel method of matching stiffness and continuous variable damping of an ECAS(electronically controlled air suspension) based on LQG(linear quadratic Gaussian) control was proposed to simultaneously improve the road-friendliness and ride comfort of a two-axle school bus.Taking account of the suspension nonlinearities and target-height-dependent variation in suspension characteristics,a stiffness model of the ECAS mounted on the drive axle of the bus was developed based on thermodynamics and the key parameters were obtained through field tests.By determining the proper range of the target height for the ECAS of the fully-loaded bus based on the design requirements of vehicle body bounce frequency,the control algorithm of the target suspension height(i.e.,stiffness) was derived according to driving speed and road roughness.Taking account of the nonlinearities of a continuous variable semi-active damper,the damping force was obtained through the subtraction of the air spring force from the optimum integrated suspension force,which was calculated based on LQG control.Finally,a GA(genetic algorithm)-based matching method between stepped variable damping and stiffness was employed as a benchmark to evaluate the effectiveness of the LQG-based matching method.Simulation results indicate that compared with the GA-based matching method,both dynamic tire force and vehicle body vertical acceleration responses are markedly reduced around the vehicle body bounce frequency employing the LQG-based matching method,with peak values of the dynamic tire force PSD(power spectral density) decreased by 73.6%,60.8% and 71.9% in the three cases,and corresponding reduction are 71.3%,59.4% and 68.2% for the vehicle body vertical acceleration.A strong robustness to variation of driving speed and road roughness is also observed for the LQG-based matching method. 展开更多
关键词 matching method electronically controlled air suspension linear quadratic Gaussian genetic algorithm
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A novel method for integrating chromatographic fingerprint analytical units of Chinese materia medica:the matching frequency statistical moment method 被引量:1
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作者 LI Haiying PAN Xue +4 位作者 WANG Mincun LI Wenjiao HE Peng HUANG Sheng HE Fuyuan 《Digital Chinese Medicine》 CAS CSCD 2024年第3期294-308,共15页
Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(M... Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(MFSM)method.Methods This study established the MFSM method.To demonstrate its effectiveness,we applied this novel approach to analyze Danxi Granules(丹膝颗粒,DXG)and its constituent herbal materials.To begin with,the ultra-performance liquid chromatography(UPLC)was applied to obtain the chromatographic fingerprints of DXG and its constituent herbal materi-als.Next,the MFSM was leveraged to compress and integrate them into a new fingerprint with fewer analytical units.Then,we characterized the properties and variability of both the original and integrated fingerprints by calculating total quantum statistical moment(TQSM)parameters,information entropy and information amount,along with their relative standard deviation(RSD).Finally,we compared the TQSM parameters,information entropy and infor-mation amount,and their RSD between the traditional and novel fingerprints to validate the new analytical method.Results The chromatographic peaks of DXG and its 12 raw herbal materials were divided and integrated into peak families by the MFSM method.Before integration,the ranges of the peak number,three TQSM parameters,information entropy and information amount for each peak or peak family of UPLC fingerprints of DXG and its 12 raw herbal materials were 95.07−209.73,9390−183064μv·s,5.928−21.33 min,22.62−106.69 min^(2),4.230−6.539,and 50530−974186μv·s,respectively.After integration,the ranges of these parameters were 10.00−88.00,9390−183064μv·s,5.951−22.02 min,22.27−104.73 min^(2),2.223−5.277,and 38159−807200μv·s,respectively.Correspondingly,the RSD of all the aforementioned pa-rameters before integration were 2.12%−9.15%,6.04%−49.78%,1.15%−23.10%,3.97%−25.79%,1.49%−19.86%,and 6.64%−51.20%,respectively.However,after integration,they changed to 0.00%,6.04%−49.87%,1.73%−23.02%,3.84%−26.85%,1.17%−16.54%,and 6.40%−48.59%,respectively.The results demonstrated that in the newly integrated fingerprint,the analytical units of constituent herbal materials,information entropy and information amount were significantly reduced(P<0.05),while the TQSM parameters remained unchanged(P>0.05).Additionally,the RSD of the TQSM parameters,information entropy,and information amount didn’t show significant difference before and after integration(P>0.05),but the RSD of the number and area of the integrated analytical units significantly decreased(P<0.05).Conclusion The MFSM method could reduce the analytical units of constituent herbal mate-rials while maintain the properties and variability from their original fingerprint.Thus,it could serve as a feasible and reliable tool to reduce difficulties in analyzing multi-compo-nents within CMMs and facilitating the evaluation of their quality. 展开更多
关键词 Chromatographic fingerprints Analytical units matching frequency statistical moment method Chinese materia medica Danxi Granule(丹膝颗粒 DXG) Quality evaluation
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SERIES PERTURBATIONS APPROXIMATE SOLUTIONS TO N-S EQUATIONS AND MODIFICATION TO ASYMPTOTIC EXPANSION MATCHED METHOD
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作者 李大鸣 张红萍 高永祥 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第8期963-972,共10页
A method that series perturbations approximate solutions to N-S equations with boundary conditions was discussed and adopted. Then the method was proved in which the asymptotic solutions of viscous fluid flow past a s... A method that series perturbations approximate solutions to N-S equations with boundary conditions was discussed and adopted. Then the method was proved in which the asymptotic solutions of viscous fluid flow past a sphere were deducted. By the ameliorative asymptotic expansion matched method, the matched functions, are determined easily and the ameliorative curve of drag coefficient is coincident well with measured data in the case that Reynolds number is less than or equal to 40 000. 展开更多
关键词 asymptotic expansion matched method series perturbation N-S equation viscous fluid flow past a sphere
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Artificial Immune Detection for Network Intrusion Data Based on Quantitative Matching Method
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作者 CaiMing Liu Yan Zhang +1 位作者 Zhihui Hu Chunming Xie 《Computers, Materials & Continua》 SCIE EI 2024年第2期2361-2389,共29页
Artificial immune detection can be used to detect network intrusions in an adaptive approach and proper matching methods can improve the accuracy of immune detection methods.This paper proposes an artificial immune de... Artificial immune detection can be used to detect network intrusions in an adaptive approach and proper matching methods can improve the accuracy of immune detection methods.This paper proposes an artificial immune detection model for network intrusion data based on a quantitative matching method.The proposed model defines the detection process by using network data and decimal values to express features and artificial immune mechanisms are simulated to define immune elements.Then,to improve the accuracy of similarity calculation,a quantitative matching method is proposed.The model uses mathematical methods to train and evolve immune elements,increasing the diversity of immune recognition and allowing for the successful detection of unknown intrusions.The proposed model’s objective is to accurately identify known intrusions and expand the identification of unknown intrusions through signature detection and immune detection,overcoming the disadvantages of traditional methods.The experiment results show that the proposed model can detect intrusions effectively.It has a detection rate of more than 99.6%on average and a false alarm rate of 0.0264%.It outperforms existing immune intrusion detection methods in terms of comprehensive detection performance. 展开更多
关键词 Immune detection network intrusion network data signature detection quantitative matching method
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AUTOMATIC DISPLACEMENT ANALYSIS OF PLANAR MECHANISMS WITH MATCHING BASIC KINEMATIC CHAINS METHOD
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作者 WangYuxin MuXihui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第2期113-116,共4页
A simple, efficient, automatic and universal method to fulfill displacementanalysis of a great deal of mechanisms regenerated by Yan's mechanism creative theory has beendeveloped. For a regenerated mechanism, at f... A simple, efficient, automatic and universal method to fulfill displacementanalysis of a great deal of mechanisms regenerated by Yan's mechanism creative theory has beendeveloped. For a regenerated mechanism, at first, the method identifies its type and structure andchanges it into a rigid structure by fixing the ground link and the input link. And then this rigidstructure is decomposed into a set of basic kinematic chains (BKCs). By matching the type of BKC,the displacement analysis equations can be set up, and all possible configurations, in whichpositions of all movable links are considered, can be given out. 展开更多
关键词 mechanism analysis computerized method matching basic kinematic chains
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REQUIREMENTS AND DESIGN METHOD FOR MATCHING AIRCRAFT GUNS WITH THEIR SUPPORTING STRUCTURE
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《Chinese Journal of Aeronautics》 SCIE EI CAS 1988年第2期105-109,共5页
In aircraft structural dynamic design the matching of guns with their supporting structure is one of the most important tasks on which hinges the success or failure of the structural design. The design curves for matc... In aircraft structural dynamic design the matching of guns with their supporting structure is one of the most important tasks on which hinges the success or failure of the structural design. The design curves for matching guns with their supporting structure can be obtained from response calculations of the plate-spring system supporting the gun on the ground,the model structure tested on the ground and the actual structure.A set of matching curves is given for engineering application.Then,the matching design can be accomplished by means of impact load spectrograms so as to perform an optimal structural design and to make further improvements on dynamic design program. 展开更多
关键词 REQUIREMENTS AND DESIGN method FOR matchING AIRCRAFT GUNS WITH THEIR SUPPORTING STRUCTURE
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Efficacy-cost analysis of endoscopic mucosal resection and cold snare polypectomy:A propensity score matching analysis
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作者 Shi-Yi Zhang Ying-Chun Wang +2 位作者 Lei-Lei Liu Zhi-Heng Wang Xue-Mei Guan 《World Journal of Gastrointestinal Surgery》 2025年第2期77-86,共10页
BACKGROUND Although substantial evidence supports the advantages of cold snare polypectomy(CSP)in terms of polypectomy efficacy and reduced postoperative adverse events,few studies have examined the cost differences b... BACKGROUND Although substantial evidence supports the advantages of cold snare polypectomy(CSP)in terms of polypectomy efficacy and reduced postoperative adverse events,few studies have examined the cost differences between CSP and traditional endoscopic mucosal resection(EMR)for the treatment of intestinal polyps.AIM To compare the efficacy-cost of EMR and CSP in the treatment of intestinal polyps.METHODS A total of 100 patients with intestinal polyps were included in the retrospective data of our hospital from April 2022 to May 2023.According to the treatment methods,they were divided into EMR(n=46)group and CSP(n=54)group.The baseline data of the two groups were balanced by 1:1 propensity score matching(PSM),and the cost-effectiveness analysis was performed on the two groups after matching.The recurrence rate of the two groups of patients was followed up for 1 year,and they were divided into recurrence group and non-recurrence group according to whether they recurred.Multivariate logistic regression analysis was used to screen out the influencing factors affecting the recurrence of intestinal polyps after endoscopic resection.RESULTS Significant disparities were observed in the number of polyps and smoking background between the two groups before PSM(P<0.05).Following PSM,the number of polyps and smoking history were well balanced between the EMR and CSP groups.The direct cost incurred by the CSP group was markedly higher than that incurred by the EMR group.Concurrently,the cost-effectiveness ratio in the CSP group was substantially reduced when juxtaposed with that in the EMR group(P<0.05).Upon completion of the 1-year follow-up,the rate of recurrence after endoscopic intestinal polypectomy was 38.00%.Multivariate methods revealed that age≥60 years,male sex,number of polyps≥3,and pathological type of adenoma were risk factors for recurrence after endoscopic intestinal polypectomy(all P<0.05).CONCLUSION CSP was more cost-effective for the treatment of intestinal polyps.An age≥60 years,male sex,having a number of polyps≥3,and pathological type of adenoma are independent influencing factors for recurrence. 展开更多
关键词 Propensity score matching method Endoscopic mucosal resection Cold snare polypectomy Intestinal polyps Curative effect Cost analysis
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Precision Comparison and Analysis of Multi-stereo Fusion and Multi-view Matching Based on High-Resolution Satellite Data
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作者 LIU Tengfei HUANG Xu HUANG Zefeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第5期577-588,共12页
High-resolution sub-meter satellite data play an increasingly crucial role in the 3D real-scene China construction initiative.Current research on 3D reconstruction using high-resolution satellite data primarily focuse... High-resolution sub-meter satellite data play an increasingly crucial role in the 3D real-scene China construction initiative.Current research on 3D reconstruction using high-resolution satellite data primarily focuses on two approaches:Multi-stereo fusion and multi-view matching.While algorithms based on these two methodologies for multi-view image 3D reconstruction have reached relative maturity,no systematic comparison has been conducted specifically on satellite data to evaluate the relative merits of multi-stereo fusion versus multi-view matching methods.This paper conducts a comparative analysis of the practical accuracy of both approaches using high-resolution satellite datasets from diverse geographical regions.To ensure fairness in accuracy comparison,both methodologies employ non-local dense matching for cost optimization.Results demonstrate that the multi-stereo fusion method outperforms multi-view matching in all evaluation metrics,exhibiting approximately 1.2%higher average matching accuracy and 10.7%superior elevation precision in the experimental datasets.Therefore,for 3D modeling applications using satellite data,we recommend adopting the multi-stereo fusion approach for digital surface model(DSM)product generation. 展开更多
关键词 multi-stereo fusion reconstruction multi-view matching reconstruction non-local dense matching method occlusion detection high-resolution satellite data
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An integrated method for matching forest machinery and a weight-value adjustment
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作者 Dan Li 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第3期683-688,共6页
Proper matching of forestry machinery is important when raising mechanization levels for forestry production. In the matching process, forestry machinery needs not only expertise, but also improved methods for solving... Proper matching of forestry machinery is important when raising mechanization levels for forestry production. In the matching process, forestry machinery needs not only expertise, but also improved methods for solving problems. I propose combination of case-based reasoning (CBR) and rule-based reasoning (RBR) by calculating the similarity of quantitative parameters of various forestry machines in an analytical and hierarchical process. I calculated the similarity of machin-ery used in forest industries to enable better selection and matching of equipment. I propose a weight-value adjusting method based on sums of squares of deviations in which the individual parameter weights were modified in the process of application. During the process of system design, I put forward a design method knowledge base and generated a dynamic web reasoning framework to integrate the processes of forest industry machinery selection and weight-value adjustment. This enables expansion of the scope of the complete system and enhancement of the reasoning efficiency. I demonstrate the validity and practicability of this method using a practical example. 展开更多
关键词 forest industry machinery Selection and matching weight-value determination reasoning process integration method
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双靶联合放疗在HER-2阳性乳腺癌保乳术后的应用
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作者 刘洋 刘晶晶 《安徽医学》 2026年第3期301-307,共7页
目的基于倾向性评分匹配法(PSM)分析双靶联合大分割放疗在人表皮生长因子受体-2(HER-2)阳性乳腺癌患者保乳术后中的应用。方法回顾性分析唐山市人民医院放化六科2021年12月至2024年6月132例行保乳术及术后辅助治疗的HER-2阳性乳腺癌患... 目的基于倾向性评分匹配法(PSM)分析双靶联合大分割放疗在人表皮生长因子受体-2(HER-2)阳性乳腺癌患者保乳术后中的应用。方法回顾性分析唐山市人民医院放化六科2021年12月至2024年6月132例行保乳术及术后辅助治疗的HER-2阳性乳腺癌患者的临床资料,采用PSM按1∶1最近邻匹配法匹配,匹配后双靶组(双靶联合大分割放疗)和单靶组(单靶联合大分割放疗)各46例患者。比较两组患者血清多肽特异性抗原(TPS)、糖类抗原153(CA153)、血管内皮生长因子(VEGF)、VEGF受体2(VEGFR2)水平差异,比较两组患者不良反应发生率及随访情况。结果相较于治疗前,治疗后6个月两组血清TPS、CA153水平均降低,相较于单靶组,双靶组治疗后6个月血清TPS、CA153水平更低(P<0.05);相较于治疗前,治疗后6个月两组血清VEGF、VEGFR2水平均降低,相较于单靶组,双靶组治疗后6个月血清VEGF、VEGFR2水平更低(P<0.05);两组不良反应发生率差异无统计学意义(P>0.05);双靶组中位随访时间为17.5个月(范围5~35个月),单靶组为17.0个月(范围5~34个月),两组中位随访时间差异无统计学意义(log-rank检验χ^(2)=0.127,P=0.725),具有良好可比性。Kaplan-Meier生存分析显示,双靶组PFS为94.4%高于单靶组的85.2%,差异有统计学意义(log-rank检验χ^(2)=4.795,P=0.029)。随访期间,双靶组未出现死亡事件,而单靶组观察到4例死亡事件,2年总生存期率略低(log-rank检验χ^(2)=2.841,P=0.092)。结论HER-2阳性乳腺癌患者保乳术后采用双靶联合大分割放疗可以提高无进展生存期,降低血清TPS、CA153、VEGF、VEGFR2水平,临床需根据患者实际病情选择合适的靶向治疗手段。 展开更多
关键词 双靶 大分割放疗 人表皮生长因子受体-2阳性 乳腺癌 保乳术 倾向性评分匹配法
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达雷妥尤单抗对输血相容性试验的影响及改良DTT法消除干扰的研究
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作者 胡艳 卞茂红 鲍静 《临床输血与检验》 2026年第1期70-74,共5页
目的探究多发性骨髓瘤患者(multiple myeloma,MM)应用达雷妥尤单抗(daratumumab,DARA)治疗后对输血相容性试验的影响,并用改良DTT法消除干扰。方法收集11例在我院应用DARA治疗的MM患者样本,观察DARA治疗对不规则抗体筛查检测和交叉配血... 目的探究多发性骨髓瘤患者(multiple myeloma,MM)应用达雷妥尤单抗(daratumumab,DARA)治疗后对输血相容性试验的影响,并用改良DTT法消除干扰。方法收集11例在我院应用DARA治疗的MM患者样本,观察DARA治疗对不规则抗体筛查检测和交叉配血试验的影响;用经典DTT法及改良DTT法分别处理抗筛细胞与供者红细胞后,微柱凝胶法进行不规则抗体筛查和交叉配血试验;评估输血效果并观察输血不良反应。结果所有患者经DARA治疗后,微柱凝胶法不规则抗体筛查与交叉配血主侧均呈阳性反应,凝聚胺法检测为阴性反应;改良DTT法处理抗筛细胞与供者红细胞,0.02 mol/L DTT可使微柱凝胶法抗筛与交叉配血主侧均呈阴性反应,可正确检出抗K抗体;输血治疗后患者血红蛋白水平均有不同程度的升高(P<0.05),血清间接胆红素水平无明显变化(P>0.05),表明输血治疗有效,所有患者均未出现严重输血不良反应。结论DARA治疗可对输血相容性检测产生干扰,可选用改良DTT法进行微柱凝胶法抗筛与交叉配血,保证患者输血的及时性、安全性和有效性。 展开更多
关键词 达雷妥尤单抗 多发性骨髓瘤 改良DTT法 微柱凝胶法 交叉配血
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基于倾向性匹配评分法分析达芬奇机器人与传统腹腔镜下远端根治术治疗胃癌的临床价值
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作者 薛钧泽 王昆 +4 位作者 林浩 张益豪 焦学龙 谭晓杰 江海涛 《川北医学院学报》 2026年第1期24-28,共5页
目的:基于倾向性匹配评分法分析达芬奇机器人与传统腹腔镜下远端根治术治疗胃癌的临床价值。方法:收集接受远端胃癌根治术的胃癌患者的病历资料,按照手术方式不同分为机器人组(达芬奇机器人手术,n=85)和腹腔镜组(传统腹腔镜手术,n=81)... 目的:基于倾向性匹配评分法分析达芬奇机器人与传统腹腔镜下远端根治术治疗胃癌的临床价值。方法:收集接受远端胃癌根治术的胃癌患者的病历资料,按照手术方式不同分为机器人组(达芬奇机器人手术,n=85)和腹腔镜组(传统腹腔镜手术,n=81)。采用倾向性匹配评分法(1∶1最近邻匹配,卡钳值0.2)平衡一般资料,最终获得每组63对患者进行手术,术后随访6个月。比较两组患者围术期指标(手术时间、淋巴结清扫数目、术后首次流质饮食时间、腹腔引流量、术后首次肛门排气时间、术后下床活动时间、术后住院时间)、炎症因子[C反应蛋白(CRP)、降钙素原(PCT)、血小板与淋巴细胞比值(PLR)、中性粒细胞与淋巴细胞比值(NLR)、白细胞计数(WBC)]、肿瘤标志物[癌抗原19-9(CA19-9)、癌胚抗原(CEA)]、术后并发症发生情况及复发情况。结果:治疗后,机器人组患者淋巴结清扫数目、首次肛门排气时间、腹腔引流量、术后下床活动时间均优于腹腔镜组(P<0.05);PLR、WBC、NLR、PCT、CRP低于腹腔镜组(P<0.05)。两组患者CA19-9、CEA水平、复发率、并发症发生率比较,差异无统计学意义(P>0.05)。结论:达芬奇机器人手术可提升手术效率和淋巴结清扫效果,减少术后炎症反应,且不增加术后风险。 展开更多
关键词 倾向性匹配评分 达芬奇机器人手术 传统腹腔镜手术 胃癌 应用价值
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基于RFID短路短截线贴片天线的无源无线应变传感及其小型化研究
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作者 王其昂 刘泉 +3 位作者 倪一清 马占国 丁北斗 隆劲豪 《东南大学学报(自然科学版)》 北大核心 2026年第3期417-423,共7页
为解决传统传感器布线复杂、能源依赖及维护成本高等问题,提出了一种基于射频识别(RFID)技术的无源无线应变传感及其小型化设计方法。借助HFSS软件进行仿真分析,完成了RFID短路短截线贴片天线应变传感器设计,并利用曲流开槽与短路加载... 为解决传统传感器布线复杂、能源依赖及维护成本高等问题,提出了一种基于射频识别(RFID)技术的无源无线应变传感及其小型化设计方法。借助HFSS软件进行仿真分析,完成了RFID短路短截线贴片天线应变传感器设计,并利用曲流开槽与短路加载技术进行小型化设计。通过多物理场仿真分析,证实RFID传感器谐振频率与自身应变之间存在线性关联,最终开展方向性测试、拉伸应变测试以及弯曲应变测试等验证试验。结果表明:所设计RFID贴片天线传感器,其谐振频率与应变呈较强线性关系,小型化后该传感器贴片天线面积仅为原面积的66.4%,同时具有较大无线传输距离;与有线应变测量结果相比,RFID传感器测试误差较小,从而验证了其在实际结构健康监测中的适用性。 展开更多
关键词 结构健康监测 RFID贴片天线 无线传感 无源传感 短路短截线匹配法
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FAST IMAGE ENCODING ALGORITHM BASED ON MEAN-MATCH CORRELATION VECTOR QUANTIZATION 被引量:1
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作者 徐润生 许晓鸣 张卫东 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第1期40-43,共4页
A mean-match correlation vector quantizer (MMCVQ) was presented for fast image encoding. In this algorithm, a sorted codebook is generated regarding the mean values of all codewords. During the encoding stage, high co... A mean-match correlation vector quantizer (MMCVQ) was presented for fast image encoding. In this algorithm, a sorted codebook is generated regarding the mean values of all codewords. During the encoding stage, high correlation of the adjacent image blocks is utilized, and a searching range is obtained in the sorted codebook according to the mean value of the current processing vector. In order to gain good performance, proper THd and NS are predefined on the basis of experimental experiences and additional distortion limitation. The expermental results show that the MMCVQ algorithm is much faster than the full-search VQ algorithm, and the encoding quality degradation of the proposed algorithm is only 0.3~0.4 dB compared to the full-search VQ. 展开更多
关键词 image coding vector quantization mean match method
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妊娠期糖尿病与剖宫产术腰麻后低血压关系的研究
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作者 杨璐瑶 马庆玲 +3 位作者 庞昀婷 梁亚楠 刘伟 孟凡青 《现代妇产科进展》 2026年第2期109-113,119,共6页
目的:应用倾向性评分匹配(PSM)法探讨妊娠期糖尿病(GDM)与剖宫产术腰麻后低血压的关系,为识别腰麻后低血压的高危人群,降低母婴围产期不良反应发生率提供科学依据。方法:前瞻性收集2023年10月至2024年10月择期在腰硬联合麻醉下行剖宫产... 目的:应用倾向性评分匹配(PSM)法探讨妊娠期糖尿病(GDM)与剖宫产术腰麻后低血压的关系,为识别腰麻后低血压的高危人群,降低母婴围产期不良反应发生率提供科学依据。方法:前瞻性收集2023年10月至2024年10月择期在腰硬联合麻醉下行剖宫产术的单胎产妇210例,年龄18~40岁,孕37~42周,ASA分级Ⅱ或Ⅲ级。根据是否合并GDM将患者分为两组,GDM组(70例)与非GDM组(140例)。通过PSM对两组进行相关变量匹配,成功配对56对。比较两组低血压的发生情况及新生儿结局。结果:PSM前,GDM组的生产时BMI、体重增加值、腹围高于非GDM组(P<0.05);PSM后,两组的一般资料比较,差异均无统计学意义(P>0.05)。结局指标分析:PSM前,GDM组的去甲肾上腺素用量、新生儿体重高于非GDM组,新生儿血糖低于非GDM组(P<0.05);PSM后,GDM组的新生儿体重高于非GDM组,新生儿血糖低于非GDM组,差异有统计学意义(P<0.05)。两组各时间点MAP及HR比较,差异无统计学意义(P>0.05)。结论:GDM未增加剖宫产术腰麻后低血压的发生。 展开更多
关键词 妊娠期糖尿病 剖宫产术 腰麻后低血压 倾向性评分匹配法
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北京微震事件检测与分析
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作者 钟慧婷 边银菊 +2 位作者 任梦依 王婷婷 张艺潇 《地震学报》 北大核心 2026年第2期324-338,共15页
为完善北京市门头沟区和房山区的矿震事件记录,提升微震事件识别的完整性与可靠性,对两区的矿震检测及特征展开研究。从北京遥测数字地震台网和中国地震台网中心选取8个矿震事件作为模板事件,首先利用模板匹配技术(M&L)检测2016年1... 为完善北京市门头沟区和房山区的矿震事件记录,提升微震事件识别的完整性与可靠性,对两区的矿震检测及特征展开研究。从北京遥测数字地震台网和中国地震台网中心选取8个矿震事件作为模板事件,首先利用模板匹配技术(M&L)检测2016年1月—2017年12月的遗漏矿震事件,经筛选得到280个事件;其次重新分析了这些遗漏事件与模板事件的相关性;最后对这些事件的震级、发震时间、波形特征及互相关系数等参数进行了综合分析。结果显示:新检测矿震事件数量远多于地震台网中心正式编目事件,且与模板事件具有较高相关性,证实了M&L方法在该区域微震事件识别中的有效性;检测事件震级均在M3.0以下,以M1.5—2.5为主;发震时间分布较为分散,未呈明显的规律性,排除了人为活动引发的可能性。时频图分析显示,这些事件的波形整体衰减缓慢,面波较为发育,以低频为主,符合矿震的典型时频特征;每年检测结果中事件两两之间的互相关系数计算结果显示大多数事件的互相关系数都在0.5以上。 展开更多
关键词 模板匹配定位方法 非天然地震 矿震特征 互相关
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自适应通信网络信道衰减特性建模分析
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作者 仇珏 林霞 +2 位作者 刘晓捷 李佳 边小军 《微型电脑应用》 2026年第1期311-316,共6页
在信号传输过程中信号衰减程度较为严重,会导致电力物联网终端设备通信的可靠性更差,为此研究自适应通信网络信道衰减特性建模方法,精准建模、分析多径、频率等与信道衰减特性的关系。利用多径传播模型分析多径传播对信道线路衰减特性... 在信号传输过程中信号衰减程度较为严重,会导致电力物联网终端设备通信的可靠性更差,为此研究自适应通信网络信道衰减特性建模方法,精准建模、分析多径、频率等与信道衰减特性的关系。利用多径传播模型分析多径传播对信道线路衰减特性的影响,根据时变传输线原理获取线路损耗导致线路衰减的原因,分析信号频率、传输距离对线路衰减特性的影响;采用矢量匹配法建模分析信道耦合衰减特性。实验结果表明所提出的方法可精准建模分析信道衰减特性。频率越大,信道幅频与相频衰减程度越大,当频率低于0.75 MHz时,信道衰减情况较轻,通信质量较佳;传输距离越大,信道幅值下降程度越大,相位角衰减越快,通信质量越差;电阻越大,信道耦合衰减程度越小,当电阻为14Ω时,耦合衰减值最小,通信质量最佳。 展开更多
关键词 通信网络 信道衰减特性 建模分析 多径传播 矢量匹配法
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含凹坑缺陷承压结构的安定、棘轮及低周疲劳行为分析
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作者 李佳琳 王骁晓 陈浩峰 《压力容器》 北大核心 2026年第1期43-55,共13页
针对压力容器常在高温、高压及腐蚀性介质等恶劣工况下运行时,凹坑、裂纹等缺陷显著降低其承载能力并引发安全事故的关键问题,采用线性匹配法(LMM)系统分析了高温承压结构中凹坑缺陷的几何特征对疲劳行为的影响机制。研究结果表明,局部... 针对压力容器常在高温、高压及腐蚀性介质等恶劣工况下运行时,凹坑、裂纹等缺陷显著降低其承载能力并引发安全事故的关键问题,采用线性匹配法(LMM)系统分析了高温承压结构中凹坑缺陷的几何特征对疲劳行为的影响机制。研究结果表明,局部减薄凹坑会显著降低反向塑性极限,其中沿容器轴向的局部减薄凹坑影响程度最大,而椭圆形凹坑的极限载荷基本不受凹坑尺寸的影响;在高温环境下,轴向局部减薄凹坑使总应变范围增加53.8%,周向局部减薄凹坑仅使总应变范围增加18.1%;椭圆形凹坑的总应变范围受凹坑尺寸影响显著,其随短轴(轴向尺寸)增大而增大,随长轴(周向尺寸)增大而减小。研究可为延长设备使用寿命、提高生产效率提供理论参考。 展开更多
关键词 压力容器 凹坑缺陷 线性匹配法 疲劳寿命
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Ground motion,liquefaction and hazard analysis at the Palu site during the 2018 Indonesian great earthquake(M_(w)7.5)
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作者 Lindung Zalbuin Mase Weeradetch Tanapalungkorn +2 位作者 Suched Likitlersuang Kyohei Ueda Tetsuo Tobita 《China Geology》 2026年第1期152-174,共23页
The research findings on the ground motion and liquefaction potential analyses during the 2018 Great Indonesia Earthquake(M_(w)7.5)are significant and crucial.The earthquake triggered soil-structure damage due to liqu... The research findings on the ground motion and liquefaction potential analyses during the 2018 Great Indonesia Earthquake(M_(w)7.5)are significant and crucial.The earthquake triggered soil-structure damage due to liquefaction.This study,which thoroughly investigated four sites at Palu,was conducted by performing a comprehensive ground motion parameter analysis.The ground motion characteristics were presented and justified,particularly for the most impacted direction.Ground motion predictions were analysed to define the spectral accelerations,and matching spectral accelerations were conducted to produce ground motions for each site.Non-linear seismic ground response analysis based on the hyperbolic model of pressure pressure-dependent was performed to investigate cyclic soil behaviour.The results revealed that ground motion is crucial in significant soil damage,and the earthquake energy could trigger deep liquefaction.As the most significant ground motion,the vertical ground motion is essential in determining deep liquefaction.The discussion on the impact of liquefaction based on the results of the numerical analysis is presented.Significant ground motion with a longer duration could have a substantial impact on deep liquefaction in the study area.These findings depict how the 2018 Indonesia Earthquake(M_(w)7.5)triggered a mega-liquefaction in Palu City.The results could enhance the understanding of the importance of seismic hazard assessment.It is recommended that site investigation and soil improvement should be planned to counteract liquefaction damage before construction.This study also suggests conducting seismic hazard assessments for city development to minimise the potential disaster impact in the study area. 展开更多
关键词 Shallow earthquake(Mw 7.5) Ground motion LIQUEFACTION Spectral matching method Seismic Hazard Assessment Structure damage
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地铁车站SP-TS管幕工法支护参数对地表沉降的影响
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作者 柏谦 李征 +1 位作者 赵文 彭志鹏 《隧道建设(中英文)》 北大核心 2026年第1期103-112,共10页
为解决现有的暗挖工法在修建地铁车站时面临的地层变形控制困难、施工周期长、工序复杂等问题,提出一种将小直径管幕与地铁车站永久顶板结构相结合的协同支护方法——小直径管幕顶板法(SP-TS工法)。以沈阳地铁3号线和平南大街站为工程背... 为解决现有的暗挖工法在修建地铁车站时面临的地层变形控制困难、施工周期长、工序复杂等问题,提出一种将小直径管幕与地铁车站永久顶板结构相结合的协同支护方法——小直径管幕顶板法(SP-TS工法)。以沈阳地铁3号线和平南大街站为工程背景,首先,系统阐述该工法建设地铁车站的具体施工步骤;然后,建立经现场监测数据验证的三维数值模型,分析暗挖长度、车站跨度、管幕刚度及顶板弹性模量等参数对地表沉降的影响规律;最后,通过正交试验设计和多元线性回归方法,构建不同暗挖长度、车站跨度下,支护参数(管幕刚度、顶板弹性模量)与地表沉降之间的定量预测模型。研究结果表明:1)地表沉降在顶板施工阶段最为显著,是该工法沉降控制的关键环节;2)地表沉降随暗挖长度和车站跨度的增加呈对数增长,而随管幕刚度和顶板弹性模量的增加呈对数减小,其中管幕刚度的影响更为突出,将其刚度值由EI提升至2EI时可减少沉降约8.2 mm;3)基于多元回归分析构建的沉降预测模型,给出不同跨度与暗挖长度下地铁车站的分级支护参数匹配方案。 展开更多
关键词 小直径管幕顶板法 参数匹配 地铁车站 地表沉降 数值模拟
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